A major earthquake has hit TC39, the JavaScript standards committee. A proposal for adding type annotations to JavaScript has just landed in the committee, and has been approved for Stage 1. What is this proposal all about? How did it come to be? What is the motivation behind it? What are its pros and cons? Why are some people excited about it, some wary, some angry, and some afraid? As one of the writers of this proposal, I will delve into the details of the proposal, and try to answer all the questions above. https://jsconfbp.com/speakers/gil-tayar About Gil 30 years of experience have not dulled the fascination Gil Tayar has with software development. His passion is distributed systems and figuring out how to scale development to big teams. Extreme modularity and testing are the main tools in his toolbelt, using them to combat the code spaghetti monster at companies like Wix, Applitools, and at his current job as software architect at Roundforest. In his private life, he is a dad to two lovely kids (and a cat), an avid reader of Science Fiction, (he counts Samuel Delany, Robert Silverberg, and Robert Heinlein as favorites) and a passionate film buff. (Stanley Kubrick, Lars Von Trier, David Cronenberg, anybody?) Unfortunately for him, he hasn’t answered the big question of his life—what’s better, static or dynamic languages? But he’s working on it.